Underwater well guide system



g- 1964 L. G. OTTEMAN ETAL 3,143,171

UNDERWATER WELL GUIDE SYSTEM Filed April 11, 1961 3 Sheets-Sheet 1 X (II) INVENTORS:

J. A. HAEBER L. G. OTTEMAN ,Hrw

HEIR AGENT g- 1964 L. G. OTTEMAN ETAL 3,

UNDERWATER WELL GUIDE SYSTEM Filed April 11, 1961 3 Sheets-Sheet 2 53 54 55- wse FIG.2

INVENTORSZ J. A. HAEBER L. G. OTTEMAN BY! S AGENT Aug. 1964 L. G. OTTEMAN ETAL 3,143,171

UNDERWATER WELL GUIDE SYSTEM Filed April 11, 1961 3 Sheets-Sheet 3 Fl G 5 INVENTORS i J. A HAEBER L. G. OTTEMAN BY: Q T EIR AGENT United States Patent '0 3,143,171 UNDERWATER WELL GUIDE SYSTEM Lloyd G. Otteman and John A. Haeber, Houston, Tex., assignors to Shell Gil (Zompany, New York, N.Y., a corporation of Delaware Filed Apr. 11, 1961, Ser. No. 102,222 10 Claims. (Cl. 166-665) This invention relates to apparatus for use at offshore well installations and pertains more particularly to a guide system adapted to extend from an operational base above the surface of a body of water to the wellhead support structure which is located underwater and preferably on the ocean floor. The present apparatus further pertains to a guide system for guiding various wellhead compoents or devices down to a wellheadstructure on the ocean floor where the components and devices are accurately aligned with other well members, for example, a casinghead, already'positioned on the wellhead support base.

In an attempt to locate new oil fields, an increasing amount of well drilling has been conducted at offshore locations, such for example, as oil the coasts of Louisiana, Texas, and California. As a general rule, the strings of casing in a well together with the tubing string or strings extend to a point well above the surface of the water where they are closed in the conventional manner that is used on land wells, with a conventional wellhead assembly being attached to the top of the casing. Attempts have been made recently to'provide methods and apparatus for drilling and completing a well wherein both the well casinghead and subsequently the wellhead assembly and the casinghead closure device are located underwater at a depth sufiicient to allow ships to pass overthem. Preferably, the casinghead and wellhead closure assemblies are located close to the ocean floor. In order to install equipment of this type underwater in depths greater than the shallow depth at which a diver can easily operate, it has been necessary to design entirely new equipment for this purpose. Thus, during the drilling and completing of an oil or gas well at an offshore location in the manner described in copending patent application Serial No. 830,538, filed July 30, 1959, and entitled Underwater Well Completion Method, of which this application is a continuation-in-part, the various pieces of equipment employed in drilling and completing the well may be lowered from an operational base above the surface of the water to the wellhead on the ocean'fioor by means of the guide system of the present invention.

It is an object of the present invention to. provide apparatus'whereby heavy and cumbersome pieces of well drilling equipment normally used on a wellhead during drilling operations, may be lowered from a drilling barge or platform to a wellhead at the ocean floor.

Another object of the present invention is to provide apparatus whereby a piece of wellhead apparatus being lowered into place on an underwater wellhead structure will be acurately aligned with the Well casinghead so that the apparatus may be readily connected to the casinghead from a remote location.

Another object of the present invention is to provide a guide system including apparatus for maintaining in coaxial alignment a multiple number of wellhead components or all of the'wellhead components that are necessarily stacked one above the other at a wellhead during any of the drilling, completion or production operations.

These and other objects of this invention will be understood from the following description taken with reference to the drawing, wherein:

FIGURE 1 is a diagrammatic view illustrating a floating barge anchored to the ocean floor over a drilling location while a String of Well casing is being guided down into position within a well casinghead;

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FIGURE 2 is a diagrammatic View taken in partial longitudinal cross-section of a well support base having a casinghead or othertubular well member centrally located and extending upwardly therefrom while the well base is provided with guide means in accordance with the present invention which are of a height sufficient to accommodate multiple guide elements stacked one above the other;

FIGURE 3 is an isometric view of one form of the present guide system with a wellhead component being illustrated as being lowered into place on the wellhead;

FIGURE 4 is a plan view of the equipment and guide system shownin FIGURE 3; and,

FIGURE 5 is a detailed view of a guide element passing through a guide column of the present system.

Referring to FIGURE 1 of the drawing, a drilling barge 11 of any suitable fixed or floatable type is illustrated as floating on the surface of a body of water 12 and substantially fixedly positioned over a preselected location by being anchored to the ocean floor 13 by anchor lines 14 and 15 running to anchors (not shown) sunk in the ocean floor. Equipment of this type may be used when carrying out well drilling, well completion, or well maintenance operations in water varying from about to 1500 feet or more in depth. The drilling barge is equipped with a suitable derrick 16 containing fall lines 17 and a hoist 18, as well as other auxiliary equipment needed during the drilling or servicing of a well. Thus, in this instance the drilling rig is shown as being pro vided with a traveling block 21 to which is secured a pair of elevators 22 or other suitable means for connecting to the top of a string of pipe '23, commonly known as a running pipe string or running string by-which equipment may belowered down to or intoa well.

The derrick l6 ispositioned over a drilling slot or Well 26 which extends vertically through the barge 11 in a conventional manner. When using the equipment of the present invention, the slot 26 and the barge 11 may be either centrally located or extend in from oneedge. However, operations with the apparatus of the present invention may be carried out overthe'side of the barge Without the use of the slot.

An underwater wellhead support base, which is represented by a horizontally-extending support base or other frame 27, which may have a casinghead 28 secured thereto and centrally positioned in a hole in the center of the frame 27, is illustrated as being anchored to the ocean floor by means of a conductor pipe or surface casing 30 which is installed in, and preferably cemented in, the ocean floor. Secured to the wellhead support base 27 are upright aligning means having spaced vertical aligning slots therein with a, guide cablesecured at its lower end to the support base adjacent each slot. In the arrangement shown two or more guide columns 32 and 33 having guide cables 34 and 35 extend vertically therefrom to the drilling barge 11 Where they are preferably secured to the barge by means of constant-tension winches 36 and 37. The guide cables 34 and 35 are provided for the purpose of guiding pieces of equipment from the barge 11 to the guide columns 32 and 33 which guide the equipment into alignment on or in the casinghead 28 positioned at the ocean floor.

In FIGURE 1, a well connector 40 is shown as being lowered onto the casinghead 28 by means of a running pipe string 23 which extends to the barge 11 and is suspended by means of the elevators 22. The well connector 40 has -a blowout, preventer 41 fixedly secured to the top thereof. During the lowering operation, the blowout preventer 41 is secured to a connector device 42 of any suitable type in a releasable mannen'the connector device 42 in turn being fixedly secured to the lower end of the pipe string 23. Extending outwardly from the connector device 42 are a pair of guide arms 43 and 44- having guide elements 45 and 46 secured to the outer ends thereof and slidably mounted on the guide lines 34 and 35, respectively. The blowout preventer 41 is also provided with a pair of guide arms 43a and 44a having guide elements or cones 45a and 45a.

In a more detailed view of a wellhead shown in FIG- URE 2, guide line anchoring rings 47 and 48 are shown as being affixed to the support base 27 Within the guide columns 32 and 33 to anchor the guide lines 34 and 35 to the support base 27. Any suitable type of anchoring means may be used to anchor the bottoms of the guide lines to the support base in a fixed or releasable manner. A releasable guide line anchor may be of the type shown and described in copending patent application Serial No. 43,576, filed July 18, 1960, now US. Patent 3,050,139. From FIGURE 2 it may be seen that each of the guide columns 32 and 33 are provided with a longitudinal slot 51 and 52, respectively, through the wall of the tubular column, which slots are in line with the axis through the center of the well or wellhead components to be positioned thereabove.

The slots 51 and 52 are large enough in width so that the guide arms 43, 44, 53 and 54 are able to slide downwardly through the slot. While the guide elements or cones 45, 46, 55 and 56 are retained within the tubular guide columns 32 and 33, respectively. In FIGURE 2 the guide arms 53 and 54 shown as being connected to and extending laterally from a blowout preventer 57 which is rigidly flanged to a suitable connector device 58 which is actuated by providing a pressure fluid through conduits 61 or 62. Since the blowout preventer 57 and the wellhead connector 58 do not form an important part of the present invention they will not be further described in detail.

A three-column guide system is illustrated in FIGURES 3 and 4 with the columns 65, 66 and 67 being reinforced throughout their length by a circular vertical wall member 63 which takes the form of an open-top tank having an upwardly and outwardly sloping flange 64 thereon. In this particular arrangement the guide columns or tubes 65, 66 and 67 are attached to the outside of the tank or container 63, as by welding, in order to give greater clearance within the tank itself. Preferably, each of the guide columns 65, 66 and 67 has a cone-shaped flange 71, 72 and 73 attached to its upper end which serves to align guide elements or cones 74, 75 and 76 as they move downwardly into the guide columns. Each of the guide cones or elements 74, 75 and 76 is provided with a vertical hole therethrough of a diameter slightly larger than the guide cables 77, 78 and 79, thus allowing the guide elements 74, 75 and 76 down the cables and rest within their respective guide columns 65, 66 and 67.

The vertical wall member or tank 63, as well as the adjacent walls of the fixedly secured guide columns 65, 66 and 67 are provided with slots 81, 82 and 83 therein in order to enable the arms 84, 85 and 86 to pass therethrough. The slots 81, 82 and 83 are preferably smaller than the diameter of the guide cables 77, 78 and 79 in order to hole the cables in the columns 65, 66 and 67. However, in the event that it is desired to use a guide cable that is substantially smaller than the slot in the guide column, a plurality of beads may be secured in spaced relationship to each other along that portion of the guide cable within the guide column, as shown in FIGURE 5. The metal beads 87 have a diameter which is greater than the slot 83 thus preventing the cable 79 from coming out the slot. At the same time the beads 87 are small enough to pass through the vertical bore 88 in the guide element 76. By employing a wider slot 83 in the guide column 67, a more substantial guide arm 86 may be employed for connecting the guide element 76 to a well component being lowered into place. Accurate alignment of the wellhead components one above the other may be achieved by employing guide arms that fit rather snugly within the slots of the guide columns or by providing guide elements or cones whose outside diameter is substantially equal to that of the inside diameter of the guide columns. It is preferred that the guiding and aligning be primarily carried out by the interaction of the guide arms and the slots in the guide columns rather than by the interaction of the guide cone elements with either the guide lines of the interior walls of the guide columns. It is realized that any other suitable type of bracing may be employed for the guide columns 65, 66 and 67 which would replace the function of the supporting wall member 63.

We claim as our invention:

1. Apparatus for guiding wellhead equipment from an operational base above the surface of a body of water to a predetermined point below the surface of the water, said apparatus comprising a support base positioned below the surface of the Water, a plurality of tubular guide columns with the lower ends thereof being fixedly secured to said support base at spaced distances about an axis, a flexible guide line fixedly secured to each of said guide columns below the top thereof and substantially coaxial therewith, said guide lines extending upwardly through said water to said operational base thereabove, and means carried on said operational base and connected to said guide lines for supporting the upper ends thereof, each of said tubular guide columns having a longitudinal aligning slot therein in line with a radius line of the axis of said support base, said guide columns and said longitudinal slots being adapted to receive cooperating guide means in the upper end thereof.

2. Apparatus for guiding wellhead equipment from an operational base above the surface of a body of water to a predetermined point below the surface of the water, said apparatus comprising a support base positioned below the surface of the water, a plurality of tubular guide columns with the lower ends thereof being fixedly secured to said support base at spaced distances about an axis, a flexible guide line fixedly secured to each of said guide columns below the top thereof and substantially coaxial therewith, said guide lines extending upwardly through said water to said operational base thereabove, means carried on said operational base and connected to said guide lines for supporting the upper ends thereof, tubular guide elements of an outer diameter less than the inner diameter of said guide columns slidably mounted on said guide lines for movement therealong, a plurality of support arms, one end of each of said arms secured to and rigidly positioning a guide element a fixed radial distance from the vertical axis of said hole in said support base, the other ends of said arms being afiixed to a wellhead component to be guided into place above said support base, each of said tubular guide columns having a longitudinal slot therein in line with a radius line of the hole in said support base and in a position to receive one of said support arms.

3. Apparatus for guiding wellhead equipment from an operational base above the surface of a body of water to a predetermined point below the surface of the water, said apparatus comprising a support base positioned below the surface of the water, a plurality of tubular guide columns with the lower ends thereof being fixedly secured to said support base at spaced distances about a guide axis of said support base, a flexible guide line fixedly secured to each of said guide columns below the top thereof and substantially coaxial therewith, said guide lines extending upwardly through said water to said operational base thereabove, means carried on said operational base and operatively connected to said guide lines for supporting the upper ends thereof, tubular guide elements of an outer diameter less than the inner diameter of said guide columns coaxially slidably mounted on said guide lines for movement therealong, a plurality of support arms, one end of each of said arms rigidly positioning a guide e1ement a fixed radial distance from the vertical axis of said hole in said support base, the other ends of said arms being aflixed to a wellhead component to be guided into place along the guide axis of said support base, each of said tubular guide columns having a longitudinal slot therein in line with a radius line of the hole in said support base and in a position to receive one of said support arms, said slots being at least slightly wider than the arms that slide therein, said tubular guide columns being of a height sufficient to receive a plurality of guide elements moving in spaced relationship to each other.

4. Apparatus for guiding wellhead equipment from an operational base above the surface of a body of water to a predetermined point below the surface of the water, said apparatus comprising a support base positioned below the surface of the water, and having a hole therein for passing a well pipe therethrough anchoring means attached to said support base and extending into the earth formations below said body of water to fixedly anchor said support base, and tubular well member extending upwardly from said support base, a plurality of tubular guide columns with the lower ends thereof being fixedly secured to said support base about the hole therein, a flexible guide line fixedly secured to each of said guide columns below the top thereof and substantially coaxial therewith, said guide lines extending upwardly through said Water to said operational base thereabove, constant tension means carried on said operational base and operatively connected to said guide lines for maintaining tension thereon, tubular guide elements of an outer diameter less than the inner diameter of said guide columns coaxially slidably mounted on said guide lines for movement therealong, a plurality of support arms, one end of each of said arms rigidly positioning a guide element a fixed radial distance from the Vertical axis of said hole in said support base, the other ends of said arms being affixed to a wellhead component to be guided into place on the tubular member of said support base, each of said tubular guide columns having a longitudinal slot therein in line with a radius line of the hole in said support base, said slots being at least slightly wider than the arms that slide therein, said tubular guide columns being of a height sufiicient to receive a plurality of guide elements moving in spaced relationship to each other.

5. Apparatus for guiding equipment provided with an aligning element from an operational base above the surface of a body of water to a predetermined point below the surface of the water, said apparatus comprising (a) support base means positioned below the surface of the water,

(11) vertically-disposed rigid aligning means with the lower end thereof being fixedly secured to said support base and spaced from an axis thereof,

(c) said aligning means being provided with longitudinal aligning slot means extending downwardly from the top thereof and adapted to receive said aligning element therein, and

(d) flexible guide line means secured to said support base means adjacent said aligning slot means of said vertically-disposed aligning means, said guide line means adapted to extend upwardly through said water to said operational base thereabove.

6. The apparatus of claim 5 including means carried on said operational base and connected to said guide line means for supporting the upper ends thereof.

7. The apparatus of claim 5 including means secured to and extending substantially laterally from said aligning means adjacent said aligning slot means and substantially surrounding said guide line means at least near the top of said aligning means to limit possible displacement of the guide line means at that point.

8. Apparatus for guiding equipment from an operational base above the surface of a body of water to a predetermined point below the surface of the water, said apparatus comprising (a) support base means positioned below the surface of the water,

(b) vertically-disposed rigid aligning means with the lower end thereof being fixedly secured to said support base and spaced from an axis thereof,

(0) said aligning means being provided with a plurality of longitudinal aligning slots extending downwardly from the top thereof and each adapted to receive a cooperating aligning element therein,

(d) flexible guide line means secured to said support base means adjacent said aligning slots of said vertically-disposed aligning means, said guide line means adapted to extend upwardly through said water to said operational base thereabove,

(e) a guide element slidably mounted on said guide line means for movement therealong, and

(1) arm means extending laterally from said guide element, a portion of said arm means being of a size to extend into said aligning slot means for guided movement therealong.

'9. The apparatus of claim 8 including beads fixedly secured to said guide line means at a level adjacent the aligning slot means, said beads having a lateral dimension greater than the width of said slot means.

10. The apparatus of claim 8 wherein said verticallydisposed aligning means comprises upwardly-extending wall means adapted to surround an underwater wellhead.

References Cited in the file of this patent UNITED STATES PATENTS 2,650,068 Rand Aug. 25, 1953 2,808,230 McNeill et a1 Oct. 1, 1957 3,012,610 Bauer et al Dec. 12, 1961 

1. APPARATUS FOR GUIDING WELLHEAD EQUIPMENT FROM AN OPERATIONAL BASE ABOVE THE SURFACE OF A BODY OF WATER TO A PREDETERMINED POINT BELOW THE SURFACE OF THE WATER, SAID APPARATUS COMPRISING A SUPPORT BASE POSITIONED BELOW THE SURFACE OF THE WATER, A PLURALITY OF TUBULAR GUIDE COLUMNS WITH THE LOWER ENDS THEREOF BEING FIXEDLY SECURED TO SAID SUPPORT BASE AT SPACED DISTANCES ABOUT AN AXIS, A FLEXIBLE GUIDE LINE FIXEDLY SECURED TO EACH OF SAID GUIDE COLUMNS BELOW THE TOP THEREOF AND SUBSTANTIALLY COAXIAL THEREWITH, SAID GUIDE LINES EXTENDING UPWARDLY THROUGH SAID WATER TO SAID OPERATIONAL BASE THEREABOVE, AND MEANS CARRIED ON SAID OPERATIONAL BASE AND CONNECTED TO SAID GUIDE LINES FOR SUPPORTING THE UPPER ENDS THEREOF, EACH OF SAID TUBULAR GUIDE COLUMNS HAVING A LONGITUDINAL ALIGNING SLOT THEREIN IN LINE WITH A RADIUS LINE OF THE AXIS OF SAID SUPPORT BASE, SAID GUIDE COLUMNS AND SAID LONGITUDINAL SLOTS BEING ADAPTED TO RECEIVE COOPERATING GUIDE MEANS IN THE UPPER END THEREOF. 